Magnetic Ink Character Recognition (MICR) printing is most frequently used for checks, warrants, drafts, negotiable instruments, rebate coupons, invoices, statements, remittances, control documents, document security, to name a few. MICR ink is a ferrofluid of metallic particles. When the MICR system is not being used, ink sedimentation forms in the ink tank which may cause the system to clog. Clogging in the ink sub-tank is a primary concern and can be costly to repair. The present invention is specifically directed to inhibiting the formation of sediment in an ink sub-tank of a MICR inkjet printer.